Yes, hair is a Scrabble word!

Noun

1. A covering for the body (or parts of it) consisting of a dense growth of threadlike structures (as on the human head); helps to prevent heat loss

2. A very small distance or space

3. Filamentous hairlike growth on a plant

4. Any of the cylindrical filaments characteristically growing from the epidermis of a mammal

5. Cloth woven from horsehair or camelhair; used for upholstery or stiffening in garments

6. A filamentous projection or process on an organism